Glue pump

ABSTRACT

A PUMP OF A VERY SIMPLE CONSTRUCTION IN WHICH A PISTON IS RECIPROCATED BY A COMPRESSED AIR MOTOR WITHIN A CYLINDER WHICH MAY BE INSERTED INTO A CONTAINER FROM WHICH GLUE OR ANOTHER FLUID MAY BE DRAWN INTO THE CYLINDER AND PUMPED UNDER PRESSURE FROM THE PUMP OUTLET. THE PUMPING EFFECT IS PRODUCED BY THE RECIPROCATION OF THE PISTON IN COOPERATION WITH THE ALTERNATIVE OPERATION OF TWO CHECK VALVES ONE OF WHICH IS PROVIDED ON THE PISTON AND THE OTHER IN THE FREE LOWER END OF THE CYLINDER. THE PUMP IS DESIGNED SO AS TO PERMIT THE MOST EASILY WORN PARTS TO BE VERY EASILY AND QUICKLY EXCHANGED WHEN NECESSARY.

20, 1971 F. GEBHARDT ETAL 3,606,590

GLUE EUMPI Filed Sept. 2," 1969 .$11 111111111 Inruil,

Unted States Patent l U.S. Cl. 417-360 2 Claims ABSTRACT F THE DISCLOSURE A pump of a very simple construction in which a piston is reciprocated by a compressed air motor within a cylinder which may be inserted into a container from which glue or another iluid may be drawn into the cylinder and pumped under pressure from the pump outlet. The pumping eect is produced by the reciprocation of the piston in cooperation with the alternative operation of two check valves one of which is provided on the piston and the other in 'the free lower end of the cylinder. The pump is designed so as to permit the most easily worn parts to be very easily and quickly exchanged when necessary.

The present invention relates to a pump for drawing glue or another iuid out of a barrel or similar container and .for conveying it under pressure to any suitable place of use.

It is an objectv of this invention to provide a pump of the above-mentioned type which is of a simple construction and highly efficient in operation and designed so as to permit .the most highly stressed parts of the pump when worn to be easilyexchanged.

For attaining this object, the invention provides that the pump comprises a pump housing which is adapted to be at least partly inserted into a barrel or other container containing the glue or other viscous fluid to be conf veyed. The pump piston rod is connected at its upper end with a compressed air motor for reciprocating the piston along a cylinder chamber in the pump housing, which piston when moving in one direction is adapted to draw glue from the container into the lower part of the pump housing and, by means of alternately closing check valves, pump the glue through a ow passage including a lifting tube to a glue outlet. One feature of the invention consists in providing the pump housing and the lifting tube in the form of two separate elements, while another of its features consists in providing the two check valves at those points of the glue passage which have the largest possible cross-sectional size.

The above-mentioned feature of the invention of providing the pump housing and the lifting tube in the form of two separate elements results in a very practical construction of the new glue pump especially insofar as it permits certain parts of the pump, which are subjected to different wear, to be replaced independently of each other by new parts. The other feature mentioned above of providing the two check valves at those points of the glue passage which have the largest possible cross section permits these check valves to be made of such a "ice large size that they will cause practically no resistance to the flow of the glue through the pump.

In order to provide one of these check valves to be of the most simple construction and eilicient operation, it is another feature of the invention to provide at the inside of the free lower end of the pump housing a removable disk which forms a valve seat for the valve member of this check valve and is provided with bores which are closed by this valve member when engaging upon this seat. In order to permit this check valve when worn to be easily exchanged for another, the invention further provides this disk to be locked in its position within the open lower end of the pump housing by means of a spring ring.

For insuring that any glue which might leak through the packing around the pump piston at the upper end of the pump cylinder into the upper part of the pump Will be returned into the glue container and will normally flow back into the latter at a position underneath the upper surface of the glue within the container, the invention further provides that this packing is supported on a slide member which has a bore through which the piston rod is movable and which is thus held by the piston rod in a iixed position in the upper end of the pump chamber and is removable in a radial direction from the pump housing when the latter is withdrawn from the upper part of the pump.

According to a further feature of the invention, this slide member is provided with a channel which connects the bore in which the piston rod is slidable with the inside of the glue container into which the pump housing is inserted. This permits any glue which might have seeped out of the pump housing past the .piston rod to flow back into the glue container.

Of course, the pump according to the present invention may also be employed for conveying materials other than glue, for example, paints or enamels or even water.

The features and advantages of the present invention will become more clearly apparent from the following detailed description thereof, which is to be read with reference to the accompanying drawings, in which;

FIG. 1 shows a vertical section of a glue pump according to the invention; while FIG. '2. shows a cross section which is taken along the line II--II of FIG. l.

As illustrated in FIG. 1, the pump according to the invention which is adapted to be inserted into a barrel or other vessel containing Iglue or another viscous iluid or even water comprises a compressed air motor 2 in its upper part and a pump housing 3 in its lower part which is shown as projecting into a glue barrel 1.

The lower part of the housing of the compressed air motor 2 is secured by screws 4 to a flange 6 which forms the upper end of a tubular part 8. The wall of this tubular part 8 is provided with an aperture 10 through which the cylindrical interior of this tubular part is accessible from the outside. At its lower end the tubular part 8 is provided with an end wall 12 which contains a bore 14 the axis of which is laterally offset and parallel to the axis of the tubular part 8. Parallel to this bore :14 extends a socket bore 16 which is connected with another bore 20 which extends at a right angle thereto in a lateral outlet socket 18 which may be connected, for example, by a hose, to the place of use of the glue or other fluid.

Each bore 14 and 16 is provided with a concentric recess into which a tube 22 or 24, respectively, is tightly fitted. These tubes 22 and 24 form the connection between the tubular part 8 and the pump housing 3. Adjacent to the area of the tubular part 8, that is, at the left of FIG. 1, where the wall of bore 14 has its smallest thickness, this wall is provided with a slot and a clamping bolt 26 or the like extending transversely through this slot for clamping the tube 22 tightly within the recess in the wall of bore 14.

Pump housing 3 which is rigidly connected by a pin 28 to the tube 22 comprises two tubular parts 32 and 34 which are separated from each other by a partition 30 of a considerable thickness. The upper tubular part 32 is, however, laterally oset from and parallel to the axis of the pump housing 3 and its recessed cylindrical outer surface carries the tube 22.

The partition 30 is provided with a bore 36 which is laterally offset from and parallel to the axis of the pump housing 3 and extends through the entire partition 30 and terminates into the cylindrical inside of the lower tubular part 34 of the pump housing 3 which forms the pump chamber. The upper end of the wall of bore 36 is provided with a recess into which the lower end of tube 24 is fitted which serves as a lifting tube.

The partition 30 is further provided with a central bore 38 which extends parallel to the bore 36 and the wall of which is provided approximately centrally of its length with a recess forming a chamber 40 one side of which is open radially of the pump housing 3 toward the inside of the container 1 around the pump housing. As shown in FIG. 2, this chamber 40 contains a slide member 42 which has a bore 44 which extends coaxially to the bore 38. Along these bores 3S and I44 a piston rod 46 is slidable the lower end of which is connected to a piston 50 which is slidable along the wall of the lower tubular part 34 of the pump housing 3 -which forms a cylinder 48. For tightly sealing the inside of cylinder 48 relative to the upper tubular part 32 of pump housing 3, slide member 42 is provided with packings 52 which engage with the piston rod 46. Slide member 42 is further provided with a channel 54 through which the bore 44 communicates with the inside of the container 1 around the pump housing 3. If at the operation of piston 50 any glue might pass from the cylinder 48 into or through the bore 44 of slide memebr 42, this glue may flow back into the container 1 through the channel 54 and will not settle and become set in bore 44.

Piston rod 46 to which the piston 50 is secured by a nut 56 projects through the central bore 38 in the partition 30 and through the inside of tube 22 into the cylindrical interior of the tubular part 8 where it is connected by a transverse screw 58 to the cylindrical extension of the piston of the compressed air motor 2.

Piston 50 is provided with longitudinal bores 60 which are adapted to be closed by a valve disk 62 which is movable along the piston rod 46 and forms a part of a check valve. For sealing the cylinder chamber 48 in the lower tubular part 34, piston 50 is provided with a leather packing 66 which engages into a peripheral groove of this piston.

The free end of the lower tubular part 34 of pump housing 3 which forms a suction intake carries a disk 68 which is provided with bores 70 and with a central upwardly projecting cylindrical pin 72 on which a valve disk 74 is slidable which forms a part of a check valve and serves for covering the bores 70. Disk 68 is prevented from falling out of the lower end of the tubular part 34 by a spring ring 76.

The mode of operation of the pump according to the invention is as follows:

Assuming that the piston of the compressed air motor 2 and thus also the piston 50 are in their lowest position as shown in FIG. l and the piston of motor 2 is then A moved upwardly, valve disk 74 will be lifted from the position in which it covers the bores 70 so that glue will be sucked from the container 1 through the bores 70 into the part of the cylinder chamber y48 between the valve disk 74 and piston 50, while valve disk 62 will be prevented from being lifted off its seat by the pressure of the air which is compressed above the piston 50.

When the piston of the compressed air motor 2 arrives in its upper most position, the movement of the latter will be automatically reversed. During the resulting downward movement of piston 50, valve disk 62 will be lifted olf its seat so that the glue which is held between piston 50 and valve disk 74 can flow into the part of the cylinder chamber 48 which is located above piston 50.

When the two pistons are again in their lowest positions, the direction of their movement is again reversed with the result that valve disk 74 will again be lifted olf the bores 70, while the glue which is located above the piston 50 will pass through the bore 36 in the partition 30 and through the tube 24 and the socket bore 16 into the bore 20 in the outlet socket and from the latter, for example, through a hose, to a glue delivering or applicating device, for example, a glue gun.

Since the pump housing 3 even though it is made of a wear-resistant plastic is that part of the pump which is worn more severely than all other parts, it may be very quickly exchanged for another independently of the tubes 22 and 24 by removing the spring ring 76, unscrewing the nut 56, and by knocking out the pin 28. When the pump housing 3 has been removed from the remainder of the pump and the slide member 42, which was previously locked by the piston rod in its position in chamber 40, has been laterally withdrawn from this chamber, it is also a very simple matter to exchange the packings 52 of the slide member 42.

Although our invention has been illustrated and described with reference to the preferred embodiment thereof, we wish to have it understood that it is in no way limited to the details of such embodiment but is capable of numerous modications within the scope of the appended claims.

Having thus fully disclosed our invention, what we claim is:

1. A pump having an upper part and a lower part, said upper part comprising a reciprocating motor, said lower part comprising a pump housing adapted to be at least partly inserted into a uid to be pumped, a lower section of said housing forming a cylinder and adding an intake duct through which said fluid may be drawn into said housing, a piston rod connected to said reciprocating motor, a piston mounted on the lower end of said piston rod and adapted to `be reciprocated by said motor in said cylinder, a delivery outlet on said upper part intermediate said motor and said housing, said upper part further comprising a channel connecting the upper end of said cylinder with said outlet and together with said housing forming a uid passage, a pair of check valves in the parts of the passage having the largest cross-sectional size thereof and each being adapted to act alternately to the other at each stroke of said piston so that one of such check valves is open when the other check valve is closed, a transverse partition in the upper part of said pump housing having a bore, said piston rod extending to and being slidable along said bore, a packing on said partition for sealing an annular gap between the piston rod and the wall of said bore, said housing being removably secured to said upper part of said pump, said partition having a chamber intermediate and upper and lower part of said bore and being larger than said bore, said partition further having an aperture extending from said chamber radially to said piston rod to the outside of said housing, a slide member within said chamber carrying said packing and having a second bore through which said piston rod also extends, said slide member 6 being normally held by said piston rod in a xed position References Cited in said chamber and being removable from chamber and UNITED STATES PATENTS said pump housing through said aperture when said hous- 2 277 6 41 3/1942 Harter 417 398X ing has been removed from said upper part of said pump. r 2:515956 7 /1950 Greenbe-:Iu 128 218 2. A pump as defined in claim 1, in which said second o 2,853,767 11/1958 Smith T 417 342 bore in said slide member has a diameter larger than said piston rod so as to form an annular gap between CARLTON R. CROYLE, Primary EXamiIler said piston rod and the wall of s-aid bore, said slide mem- U S C1 X R ber further having a channel connecting said gap with 10 the area outside of said housing. 417-444, 399; 91-286 

